Various electronic circuitry and gadgets exist for the control of various household appliances including telephones and radios. Such devices require interconnecting cables or wiring with which to turn down or turn off a conventional radio when the listener wishes to focus on other matters such as a received telephone call. There are also a number of remote control devices made part of entertainment centers which allow the listener to selectively turn down or turn off a stereo by pushing a button on a hand-held control unit which is operatively associated with the stereo or entertainment system. Such devices make use of infrared and radio controlled remote control devices.
Even before the advent of wireless remote control devices, apparatus for turning on and off a radio upon the answering of a telephone have been tried. U.S. Pat. No. 1,916,131 issued to W. J. Becker on Jun. 5, 1934 discloses a mechanical arm 13 which operatively moves between two contacts 14 and 16 and must invade the mechanism which actuates the bell or telephone signaling device 2. This type of device is not modular or easily installed in association with standard telephones.
U.S. Pat. No. 2,140,655 issued to C. J. Sloan on Dec. 20, 1938 also discloses a device attempting to turn off a radio when a telephone call is received. A mercury switch must be fastened to the exterior of the telephone handset 1 and strapped in such a position so that when the handset is lifted, the mercury switch is opened preventing the playing of the radio since a circuit is open. Similarly, this device is taped or fastened to the exterior of the telephone. Therefore, there is a possibility that the circuit can be opened in the event the conversationalist using the telephone chooses a reclined position as opposed to a normal standing one.
U.S. Pat. No. 2,165,693 issued to T. D. Boss on Jul. 11, 1939 discloses a mechanical switch which must be positioned between a telephone base 5 and a handset 6. When the handset 6 is cradled with the telephone base 5, the switch is activated closing the circuit allowing the radio to play. When the handset is lifted, the switch is disengaged opening the circuit and preventing the radio from playing.
U.S. Pat. No. 2,212,792 issued to A. C. Reading on Aug. 27, 1940 discloses a mechanical switching device which is operatively associated with a handset of a telephone so that when the handset is lifted a lever 10 is actuated to prevent current from flowing to the radio while the handset is disengaged from the telephone.
U.S. Pat. No. 4,425,477 issued to Paul A. Magil on Jan. 10, 1984 discloses a hardwired telephone line triggered attenuator that automatically decreases the audio output of an audio system while a telephone is being used. When the handset is removed from its cradle, an electrical signal is produced that is detected by a sensor and control means. The detected signal is applied to a relay means from where the signal interacts with an attenuation means to effectuate a predetermined decrease in the audio output level of the audio system. The attenuator automatically restores the audio output to its previous level when the handset is returned to its normal position on the telephone cradle.
Japanese Patent No. 55-135407 issued to M. Tsurumi on Oct. 22, 1988 discloses a sound volume adjuster for a speaker that automatically lowers the audio level during a telephone conversation. The adjuster consists of a telephone, a radio frequency transmitter located inside or close to the telephone and a receiver connected to a radio or television speaker. When individuals are talking over the telephone, their conversation is received by the microphone, amplified and transmitted by a radio signal generated by the transmission section. The receiver receives the signal and a control connected to the receiver automatically reduces the sound volume generated by the speaker when the telephone handset is lifted. Thus, the sound does not interfere with the telephone conversation.
There is great potential interest in the electronics consumer market for a simple, wireless easily manufactured, non-intrusive electronic device which can mute a radio when the listener decides to pick up the telephone handset from the telephone base. Also, it is desirable that the radio be able to resume playing when the handset is cradled with the telephone base. All of this must be performed without direct wire connections so as not to interfere with the placement of the telephone and stereo system to be controlled. Furthermore, it is ideal if the necessary components be compact and completely adaptable to standard telephone connections and X10 technology or AM/FM arrangements conventionally found in the current market place for such goods.
The features identified above as being desired for a telephone operated stereo shut-off system are all provided by the present invention.